I am planning on buying a 2003 Scab that came stock with 3.31 open rear with the 5.4L and 255/70/16 tires.

I am used to running my 33x12.5's with 3.55 LS rear

I am wondering if I would be fine going to 3.73 and possibly upgrading the tires to 33's someday??

How much of a job would it be to add the LS while the rear end gears were being changed?? I can have it done at dealer cost of parts, no labor charges.

Thanks

 

That all sounds like a good plan. You could even go into the 4.XX range with those tires. Installing a LS differential during a gear change is the PERFECT time. The rear end is torn down to the exact point either way. You have to remove the differential to bolt the ring gear to it, so, it's just sitting there. They just have to press 2 bearings on it and shim it back in. That also sounds like a great deal.